In mixture-compressing internal combustion engines having external ignition and internal mixture formation, stratified charge operation requires a “mixture cloud” in the region of the spark plug, which must have a particular fuel-air ratio in the ignitable region. For this purpose, fuel injectors are used which include nozzles that open to the inside or to the outside and generate a conical jet.
From German Patent Application No. 198 04 463, a fuel injection system for a mixture-compressing internal combustion engine having external ignition is known, which includes at least one fuel injector that injects fuel into a combustion chamber having a piston/cylinder design, and which is provided with a spark plug projecting into the combustion chamber. The nozzle body of the fuel injector is provided used with at least one row of injection orifices distributed across the circumference of the nozzle body. By a selective injection of fuel via the injection orifices, a jet-controlled combustion method is realized by the formation of a mixture cloud, at least one jet being aimed in the direction of the spark plug or its immediate vicinity. Additional jets ensure that an at least approximately continuous or cohesive mixture cloud is formed.
Disadvantageous in the fuel injector known from German Patent Application No. 198 04 463 is, in particular, the incomplete utilization of the available combustion chamber, which results in a low-quality mixture formation due to an air proportion that is too high, and subsequent superelevated emissions of unburned hydrocarbons caused by individual combustion misses, as well as higher fuel consumption.